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/*
* libjingle
* Copyright 2011, Google Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "talk/base/sharedexclusivelock.h"
namespace talk_base {
SharedExclusiveLock::SharedExclusiveLock()
: shared_count_is_zero_(true, true),
shared_count_(0) {
}
void SharedExclusiveLock::LockExclusive() {
cs_exclusive_.Enter();
shared_count_is_zero_.Wait(talk_base::kForever);
}
void SharedExclusiveLock::UnlockExclusive() {
cs_exclusive_.Leave();
}
void SharedExclusiveLock::LockShared() {
CritScope exclusive_scope(&cs_exclusive_);
CritScope shared_scope(&cs_shared_);
if (++shared_count_ == 1) {
shared_count_is_zero_.Reset();
}
}
void SharedExclusiveLock::UnlockShared() {
CritScope shared_scope(&cs_shared_);
if (--shared_count_ == 0) {
shared_count_is_zero_.Set();
}
}
} // namespace talk_base
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